stpncpy(3) Library Functions Manual stpncpy(3)

stpncpy - nonstring return‐offset‐pointer copy

Standard C library (libc-lc)

#include <string.h>  // see memory.h(3head)
char *stpncpy(size_t dsize;
              char dst[restrict dsize], const char *restrict src,
              size_t dsize);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

stpncpy():

    Since glibc 2.10:
        _POSIX_C_SOURCE >= 200809L
    Before glibc 2.10:
        _GNU_SOURCE

This function is equivalent to strncpy(3), but it returns a pointer to one past the last nonnull written character.

It is equivalent to


memset(mempcpy(dst, src, strnlen(src, dsize)), '\0',
       dsize - strnlen(src, dsize))

This function returns a pointer to one past the last non-null character written, that is, dest + strnlen(src, n).

For an explanation of the terms used in this section, see attributes(7).

Interface Attribute Value
stpncpy () Thread safety MT-Safe

POSIX.1-2008.

glibc 1.07. POSIX.1-2008.

See strncpy(3).

memory.h(3head), string_copying(7)

2026-08-10 Linux man-pages 6.19